Autonomous cleaning device

ABSTRACT

An autonomous cleaning device is provided. The autonomous cleaning device includes: a device body; and a drive module, a cleaning module and a sensing module, wherein the drive module, the cleaning module and the sensing module are detachably assembled to the device body, respectively.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of U.S. application Ser.No. 15/485,237, which is based on and claims priority to Chinese PatentApplication No. 201610232698.9, filed on Apr. 14, 2016, the entirecontents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a field of intelligent cleaningtechnology, and more particularly, to an autonomous cleaning device.

BACKGROUND

With the rapid development of communication technology, application ofintelligent products in daily life becomes increasingly common, and avariety of autonomous cleaning devices have emerged, such as autonomoussweeping devices, autonomous mopping devices and so on. The autonomouscleaning devices may execute cleaning operations automatically, whichbrings convenience to users. However, as the function of an autonomouscleaning device gradually becomes strong, functional modules of theautonomous cleaning device increase and an internal structure thereofbecomes more and more complex, such that when the autonomous cleaningdevice breaks down and needs repair, disassembling time and difficultyof a single machine are increased greatly, causing difficulties tomaintenance personnel.

Since defects of a random sweeping mode become troublesome and hard toignore, sweepers capable of navigation sweeping have an increasingmarket share, and more and more sweepers with a distance measuring unit,a photographing unit and a shooting unit appear in the market, but amodularity issue of these units needs to be addressed.

SUMMARY

According to an aspect of the embodiments of the present disclosure, anautonomous cleaning device is provided. The autonomous cleaning deviceincludes: a device body, a drive module, a cleaning module and a sensingmodule, in which the drive module, the cleaning module and the sensingmodule are detachably assembled to the device body, respectively.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory only,and cannot be construed to limit the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments consistent with thepresent disclosure and, together with the description, serve to explainthe principles of the present disclosure.

FIGS. 1-4 are schematic views of an autonomous cleaning device accordingto an illustrative embodiment;

FIG. 5 is a sectional view of an autonomous cleaning device according toan illustrative embodiment;

FIG. 6 is a planar exploded view of module structures of an autonomouscleaning device according to an illustrative embodiment;

FIG. 7 is a perspective exploded view of module structures of anautonomous cleaning device according to an illustrative embodiment;

FIG. 8 is an exploded view of a device body of an autonomous cleaningdevice according to an illustrative embodiment;

FIG. 9 is a schematic view of an upper housing of an autonomous cleaningdevice according to an illustrative embodiment;

FIG. 10 is a schematic view of a part of an upper housing for assemblinga sensing module according to an illustrative embodiment;

FIG. 11 is a schematic view of an upper housing assembled with a sensingmodule according to an illustrative embodiment;

FIG. 12 is a schematic view of an upper housing assembled with aprotection cover according to an illustrative embodiment;

FIG. 13 is an exploded schematic view showing a sensing module accordingto an illustrative embodiment;

FIG. 14 is a bottom view of a sensing module according to anillustrative embodiment;

FIG. 15 is an exploded view of a left drive wheel unit according to anillustrative embodiment;

FIG. 16 is a perspective view of a main brush module in a main brushassembly according to an illustrative embodiment;

FIG. 17 is an exploded view of the main brush module shown in FIG. 16;

FIG. 18 is a schematic view of a main brush of the main brush moduleshown in FIG. 16;

FIG. 19 is a perspective view of a main brush casing of the main brushmodule shown in FIG. 16;

FIG. 20 is an exploded view of a floating system holder of the mainbrush module shown in FIG. 16;

FIG. 21 is a sectional view of a cleaning module of an autonomouscleaning device according to an illustrative embodiment;

FIG. 22 is a perspective view of a primary air channel fitted with amain brush according to an illustrative embodiment;

FIG. 23 is a sectional view of a primary air channel fitted with a mainbrush chamber according to an illustrative embodiment;

FIG. 24 is an exploded view of an autonomous cleaning device accordingto an illustrative embodiment;

FIG. 25 is an exploded view of another dust box assembly according to anillustrative embodiment;

FIG. 26 is an exploded view of another dust box assembly according to anillustrative embodiment;

FIG. 27 is a top view of the cleaning module shown in FIG. 21;

FIG. 28 is a sectional view of a secondary air channel fitted with apower unit according to an illustrative embodiment; and

FIG. 29 is a right view of the cleaning module shown in FIG. 21.

DETAILED DESCRIPTION

The present disclosure will be described in detail with reference tospecific embodiments shown in the accompanying drawings. However, theseembodiments cannot be construed to limit the present disclosure, andchanges in terms of structure, method or function, made by those skilledin the art, are contained in the protection scope of the presentdisclosure.

Terms used herein in the description of the present disclosure are onlyfor the purpose of describing specific embodiments, but should not beconstrued to limit the present disclosure. As used in the description ofthe present disclosure and the appended claims, “a” and “the” insingular forms mean including plural forms, unless clearly indicated inthe context otherwise. It should also be understood that, as usedherein, the term “and/or” represents and contains any one and allpossible combinations of one or more associated listed items.

As shown in FIGS. 1 to 5, FIGS. 1-4 are schematic views of an autonomouscleaning device according to an illustrative embodiment, and FIG. 5 is asectional view of an autonomous cleaning device according to anillustrative embodiment.

The autonomous cleaning device 100 may be an autonomous sweeping device,an autonomous mopping device and so on. The autonomous cleaning device100 may include a device body 110, a sensing system 120, a controlsystem 130, a drive module 140, a cleaning system 150, an energy system160, and a human-device interaction system 170.

The device body 110 includes a forward portion 1101 and a rearwardportion 1102 in an advancing direction thereof, and has an approximatelyround shape (both front and rear ends being round). The device body 110may have other shapes, for example including but not limited to anapproximate D shape which has a square front end and a round rear end.

The sensing system 120 includes a sensing module 121 located above thedevice body 110, a buffer 122 located at the forward portion 1101 of thedevice body 110, a cliff sensor 123, an ultrasonic sensor (not shown),an infrared sensor (not shown), a magnetometer (not shown), anaccelerometer (not shown), a gyroscope (not shown), an odometer (notshown) and other sensing components, so as to provide the control system130 with various position information and motion state information ofthe device. The sensing module 121 of the present disclosure includes acamera and a laser distance sensor (LDS), but is not limited thereto.The laser distance sensor using triangulation ranging is taken as anexample for describing how to determine a position. The basic principleof triangulation ranging is based on a geometric relationship of similartriangles, which will not be described in detail.

The laser distance sensor includes a light emitting unit (not shown) anda light receiving unit (not shown). The light emitting unit may includea light source for emitting light, and the light source may include alight emitting element, such as an infrared light emitting diode (LED)for emitting infrared light or a visible light emitting diode (LED) foremitting visible light. In some embodiments, the light source may be alight emitting element capable of emitting a laser beam. This embodimentdescribes an example where a laser diode (LD) is used as the lightsource. Specifically, the light source using the laser beam may makemeasurement more accurate than other light sources, due tomonochromatic, directional and collimating properties of the laser beam.For example, compared with the laser beam, the infrared light or thevisible light emitted by the LED is affected by the surroundingenvironment (e.g. a color or texture of an object), thereby degradingmeasurement accuracy. The LD may emit a point laser to measuretwo-dimensional position information of an obstacle, or a line laser tomeasure three-dimensional position information within a certain range ofthe obstacle.

The light receiving unit may include an image sensor, on which a lightspot reflected or scattered by the obstacle is formed. The image sensormay be a set of unit pixels in a single row or multiple rows. Theselight receiving elements may convert an optical signal into anelectrical signal. The image sensor may be a complementary metal oxidesemiconductor (CMOS) sensor or a charge-coupled device (CCD) sensor.Moreover, the light receiving unit may include a light receiving lensassembly. The light reflected or scattered by the obstacle may travelthrough the light receiving lens assembly to form an image on the imagesensor. The light receiving lens assembly may include a single lens or aplurality of lenses.

A base (not shown) may be configured to support the light emitting unitand the light receiving unit that are arranged on the base and spacedapart from each other by a particular distance. In order to measureobstacles in all directions (i.e. 360 degrees) of the autonomouscleaning device, the base may be rotatably arranged to the device body110, or the base itself does not rotate, and instead the light emittingunit and the light receiving unit are rotated by providing a rotatingelement. A rotational angular velocity of the rotating element may beobtained by providing an optical coupler and a coded disk. The opticalcoupler senses tooth absences of the coded disk, and an instantaneousangular velocity is obtained through dividing a distance between thetooth absences by a time period of sliding across the distance betweenthe tooth absences. The larger the density of the tooth absences of thecoded disk is, the higher the accuracy and precision of the measurementis, but the structure is more precise and the calculation amount alsobecomes greater. Conversely, the smaller the density of the toothabsences is, the lower the accuracy and precision of the measurement is,but the structure is relatively simple and the calculation amountbecomes less, thus reducing the cost to some extent.

A data processing means (not shown) connected with the light receivingunit, for example a digital signal processor (DSP), records distancevalues of obstacles at all angles in a zero-angle direction relative tothe autonomous cleaning device, and sends the values to a dataprocessing unit of the control system 130, such as an applicationprocessor (AP) having a CPU. The CPU runs a positioning algorithm basedon a particle filter to obtain a current position of the autonomouscleaning device, and hence a map is drawn based on the position andfurther used for navigation. In some embodiments, the positioningalgorithm employs simultaneous localization and mapping (SLAM).

The laser distance sensor based on the triangulation ranging may measurea distance value at an infinitely distant place beyond a certaindistance in principle, but it is actually difficult to implement thelong distance measurement, for example, over six meters, mainly due to asize limit of the pixel unit on the sensor of the light receiving unit,and also due to influences of a photoelectric conversion speed of thesensor, a data transmission speed between the sensor and the DSPconnected thereto, and a calculation speed of the DSP. The measurementvalue obtained by the laser distance sensor in the presence of atemperature influence will encounter a change unbearable by the system,mainly because thermal expansion of a structure between the lightemitting unit and the light receiving unit causes an angle changebetween the incident light and the emergent light, and the lightemitting unit and the light receiving unit themselves have a temperaturedrift. The accumulation of deformations caused by temperature changes,vibration and other factors will affect the measurement result severelyafter a long-term use of the laser distance sensor. The accuracy of themeasurement result directly determines the accuracy of mapping, which isthe basis for further strategy implementation of the autonomous cleaningdevice and hence is particularly important.

The forward portion 1101 of the device body 110 may carry the buffer122. When a drive wheel module 141 pushes the autonomous cleaning deviceto walk on the ground in a cleaning process, the buffer 122 detects oneor more events (or objects) in a travel path of the autonomous cleaningdevice 100, via the sensing system, for example the infrared sensor. Theautonomous cleaning device 100 may control the drive wheel module 141 soas to respond to the events (or objects), for example, keeping away fromthe obstacles, based on the events (or objects) detected by the buffer122, such as the obstacles, walls, etc.

The control system 130 is provided on a circuit mainboard inside thedevice body 110, and includes a computing processor communicated with anon-transitory memory (e.g. a hard disk, a flash memory or a RAM), suchas a central processing unit and an application processor, in which theapplication processor utilizes a positioning algorithm, for exampleSLAM, to draw a real-time map of the environment where the autonomouscleaning device is, based on the obstacle information fed back by theLDS. Moreover, the control system 130 comprehensively determines acurrent working state of the autonomous cleaning device in combinationwith distance information and speed information fed back by the buffer122, the cliff sensor 123, the ultrasonic sensor, the infrared sensor,the magnetometer, the accelerometer, the gyroscope, the odometer and thelike. For instance, the autonomous cleaning device is going across adoorsill, going onto a carpet, or located at the cliff; or an upperportion or a lower portion of the autonomous cleaning device is stuck;or a dust box thereof is full; or the autonomous cleaning device islifted. The control system 130 may further give the next specific actionstrategy in the light of above different situations, to make the workingof the autonomous cleaning device more in line with the requirements ofthe owner and thus ensure a better user experience. Further, the controlsystem 130 may plan the most efficient and reasonable sweeping path andsweeping mode based on information of the real-time map drawn throughSLAM, thus improving a sweeping efficiency of the autonomous cleaningdevice greatly.

The drive module 140 may manipulate the autonomous cleaning device 100to travel across the ground based on a drive instruction having distanceand angle information, for example x, y and θ components. The drivemodule 140 includes the drive wheel module 141, and the drive wheelmodule 141 may control a left wheel and a right wheel simultaneously. Insome embodiments, the drive wheel module 141 includes a left drive wheelunit 1411 and a right drive wheel unit 1412 for more precise controlover the motion of the autonomous cleaning device. The left drive wheelunit 1411 and the right drive wheel unit 1412 are opposed to each otheralong a transverse axis defined by the device body 110. To enable theautonomous cleaning device to move on the ground more stably or have astronger moving ability, the autonomous cleaning device may include oneor more driven wheels 142 which include but are not limited to universalwheels. The drive wheel module 141 includes a travel wheel, a drivemotor, and a control circuit for controlling the drive motor, and may beconnected with a circuit for measuring a drive current and an odometer.The drive wheel module 141 may be detachably connected to the devicebody 110, thus facilitating assembling, disassembling and maintenancethereof. The drive wheel module 141 may have an offset drop-typesuspension system, and may be fastened in a movable manner, for example,attached to the device body 110 in a rotatable manner, and receive aspring offset biased downwards and away from the device body 110. Thespring offset allows the drive wheel to maintain contact and tractionwith the ground by a certain ground adhesive force, and meanwhile, acleaning element of the autonomous cleaning device 100 also touches theground with a certain pressure.

The cleaning system 150 may be configured as a dry cleaning systemand/or a wet cleaning system. As the dry cleaning system, the maincleaning function comes from a sweeping system 150 including a mainbrush structure, a dust box structure, a fan structure, an air outlet,and connecting members among the four parts. The main brush structurethat has certain interference with the ground sweeps up rubbish on theground and carries it to a dust suction port between the main brushstructure and the dust box structure, and then the rubbish is suckedinto the dust box structure by a suction gas generated by the fanstructure and passing through the dust box structure. A dedustingcapability of the autonomous cleaning device may be represented by adust pick up (DPU) efficiency, and the DPU efficiency is influenced by astructure and materials of a main brush, by a wind power utilizationrate of air channels constituted by the dust suction port, the dust boxstructure, the fan structure, the air outlet and the connecting membersamong the four parts, and by a type and a power of a fan, and thus theDPU efficiency is a complex system design issue. Compared with anordinary plug-in cleaner, enhancement of the dedusting capability ismore significant for a cleaning robot with limited energy. Because theenhancement of the dedusting capability lowers an energy requirementeffectively, i.e., the autonomous cleaning device, which originallysweeps 80 square meters of ground on one charge, may sweep 100 squaremeters of ground or even more on one charge now. Moreover, a servicelife of a battery will be extended greatly due to the reduced number ofcharge cycles, such that the frequency of replacing the battery by auser will be decreased. More intuitively and importantly, theenhancement of the dedusting capability brings the prominent andsignificant user experience, and the user may directly draw a conclusionwhether the autonomous cleaning device sweeps or wipes cleanly. The drycleaning system may further include a side brush 152 having a rotatingshaft, and the rotating shaft has a certain angle relative to theground, so as to move debris into a main brush region of the cleaningsystem 150.

The energy system 160 includes a rechargeable battery, such as a Ni-MHbattery or a lithium battery. The rechargeable battery may be connectedwith a charge control circuit, a circuit for detecting a chargingtemperature of a battery pack, and a circuit for monitoring batteryunder-voltage, and then these three circuits are connected to asingle-chip control circuit. A main machine is charged by connecting acharging electrode with a charging post, in which the charging electrodeis provided at a side of the main machine or below the main machine. Ifthe exposed charging electrode is adhered with dust, an accumulativeeffect of charge will cause melting and deformation of a plastic bodyaround the electrode in a charging process, and even lead to deformationof the electrode per se, thus failing to continue normal charging.

The human-device interaction system 170 includes keys provided on apanel of the main machine and configured for function selection by theuser. The human-device interaction system 170 may further include adisplay screen and/or an indicator light and/or a speaker that areconfigured to show the user the current state of the autonomous cleaningdevice or function options. Moreover, the human-device interactionsystem 170 may further include a mobile client program. For a cleaningdevice of a path-navigation type, a mobile client may show the user amap of an environment where the device is located, and a location of theautonomous cleaning device, so as to provide the user with richer anduser-friendlier function options.

To describe behaviors of the robot (i.e., the autonomous cleaningdevice) more clearly, directions are defined as follows. The autonomouscleaning device 100 may travel on the ground through variouscombinations of movements relative to three mutually perpendicular axes,namely, a transverse axis x, a front-rear axis y and a central verticalaxis z, which are defined by the device body 110. A forward drivingdirection along the front-rear axis y is denoted as “forward”, and arearward driving direction along the front-rear axis y is denoted as“rearward”. The transverse axis x substantially extends between theright wheel and the left wheel of the robot while passing through anaxis center defined by a central point of the drive wheel module 141, inwhich the autonomous cleaning device 100 may rotate around the axis x.When the forward portion of the autonomous cleaning device 100 inclinesupwards and the rear portion thereof inclines downwards, the autonomouscleaning device “pitches up”; when the forward portion of the autonomouscleaning device 100 inclines downwards and the rear portion thereofinclines upwards, the autonomous cleaning device “pitches down”.Moreover, the autonomous cleaning device 100 may rotate around the axisz. In a forward direction of the robot, when the autonomous cleaningdevice 100 inclines towards a right side of the axis y, the autonomouscleaning device “turns right”; when the autonomous cleaning device 100inclines towards a left side of the axis y, the autonomous cleaningdevice 100 “turns left”.

In the present disclosure, the sensing module serves as eyes of theautonomous cleaning device 100, is a sensing element of such autonomouscleaning device 100, and thus requires high precision of installation.In an existing autonomous cleaning device, the sensing module (e.g. LDS)is integrated onto the control mainboard within the device body, or isfixed to a chassis and further connected to the control mainboard by aflexible cable, but these solutions are faced with the following issues.

(1) A dimensional chain in above solutions is long and may easily resultin a bigger error of the LDS measurement data. If the LDS is installedto the mainboard or the chassis, an outer frame of the LDS further needsto be fitted with an upper housing for fixing various components, andeven with a decorative upper cover, in addition to being fitted with thecontrol mainboard or the chassis, which thus makes the dimensional chainlonger and causes a bigger error of being fitted with the outer frame ofthe LDS. The upper and lower housings and other parts have a bigmachining deformation due to their large sizes, which may make aninstallation position of the LDS inaccurate, i.e. the position of theLDS relative to a center of the whole device is not accurate, such thatdistance data fed back to the processor cannot go through coordinateconversion accurately, and hence the distance data of the robot has agreat error. The LDS has a high requirement in precision and issusceptible to temperature, stress, vibration and other factors, and thetemperature drift may appear over time, so an influence of the error,introduced in the assembling process, on the measurement data cannot beignored.

(2) The LDS is difficult to be assembled or disassembled for replacementand maintenance. Once the sensing module is damaged, the whole deviceneeds to be disassembled for maintenance or replacement of components.The user has to send the whole device back to a processor or adesignated repair point for maintenance, which not only causesmaintenance difficulties for maintenance personnel, but also leads to along maintenance cycle, thus bringing much inconvenience to the user.

Thus, the present disclosure proposes a modular scheme of the sensingmodule, a main brush assembly, a dust box assembly and the drive module.Descriptions will be made with reference to FIGS. 5 to 11 in thefollowing.

As shown in FIGS. 6 to 8, FIG. 6 is a planar exploded view of a chassisof an autonomous cleaning device according to an illustrativeembodiment; FIG. 7 is a perspective exploded view of module structuresof an autonomous cleaning device according to an illustrativeembodiment; FIG. 8 is an exploded view of a device body of an autonomouscleaning device according to an illustrative embodiment.

As shown in FIGS. 1 to 6, the autonomous cleaning device 100 includes:the device body 110, the sensing module 121, the drive module 140, acleaning module 150 and a battery module 1601. In the presentdisclosure, the drive module 140, the cleaning module and the sensingmodule 121 may be assembled to the device body 110 in a detachablemanner respectively, such that each module may be separately assembledto or detached from the device body 110.

As shown in FIGS. 7 and 8, the device body 110 includes the chassis 102,a bottom housing 101 fixed below the chassis 102, an upper housing 103fixed above the chassis 102, and an upper cover 104 fixed above theupper housing 103. The bottom housing 101 is located under the chassis102, such that on one hand water and dust on the ground may be preventedfrom entering an accommodating space of the chassis 102 and pollutinginterfaces of various modules, i.e. waterproof and dustproof, on theother hand various modules and the chassis 102 may be protected frombeing damaged by foreign impact, and finally a decorative role may beplayed. The chassis 102 serves as a primary carrier on which variousmodules are carried, so it has high requirements on various aspects ofmaterial properties, such as hardness and toughness, and machiningprecision. Besides the accommodating space for accommodating variousmodules, the chassis 102 also includes interfaces for electricalconnection and mechanical connection provided in the accommodatingspace. The interface for electrical connection is provided at a cornerof the accommodating space close to an inner side of the device body,where the interface is not susceptible to interference. The interfacefor mechanical connection is provided at a corner of the accommodatingspace close to an outer side of the device body, for example screwsarranged in a triangular form, so as to ensure strong structuralstability. The upper housing 103 is located above the chassis 102, suchthat an accommodating space is provided for carrying the LDS, in whichthe accommodating space satisfies a requirement of positioning the LDSaccurately, protects the LDS from damages by external forces, andenables the LDS to be detached with no need to disassemble the wholedevice, but only to open the upper cover 104 and the upper housing 103.Furthermore, the upper housing 103 may also serve as a protectionagainst water, dust and external forces. The upper housing 103 may beperforated to allow the dust box, the indicator light and an interactionpanel to pass, and provide an accommodating space for the cliff sensor.The upper cover 104 mainly plays a decorative role and makes littlecontribution to the structural hardness. The protective upper cover 104of the LDS protects the LDS from damages by external forces and allowsemitted light and reflected light of the laser beam to pass.

The sensing module 121 is configured as a LDS module. The drive moduleincludes the drive wheel module and at least one driven wheel, and thedrive wheel module further includes the left and right drive wheel units(1411, 1412). The present disclosure includes one driven wheel 142 forcooperating with the left and right drive wheel units (1411, 1412) todrive the device body 110 to move. The cleaning module includes afloating main brush assembly 1 and a side brush 152. The sensing module121 is assembled upwards to the upper housing 103, the drive module, thecleaning module and the battery module 1601 are assembled downwards tothe chassis 102, and the dust box assembly is assembled upwards to thechassis 102. The upper housing 103 and the chassis 102 both reservespaces used for corresponding modules and matched with the modules inshape, and side walls of the spaces are sufficiently rigid andperpendicular to the upper housing 103 and the chassis 102, thusproviding secure and solid spaces for various modules and protecting themodules from being squeezed by external forces in an extremeenvironment. The accommodating space is further provided with interfacesfor electrical connection, e.g. connecting fingers, to allow variousmodules to be electrically connected with the circuit mainboard, so asto receive control signals and feed back measurement values. Theaccommodating space is further provided with components for mechanicalconnection, such as screws and bayonets, to allow interference fit andtight connection between the modules and the upper housing.

As shown in FIG. 9, FIG. 9 is a schematic view of an upper housing of anautonomous cleaning device according to an illustrative embodiment. Thesensing module 121 is assembled to a predetermined position in the upperhousing 103, and the predetermined position refers to an accommodatingchamber 1031 fitted with the sensing module 121, i.e. the upper housing103 reserves an accommodating space for allowing the sensing module 121to be assembled thereto. The predetermined position not only satisfiesthe requirement of positioning the sensing module 121 accurately, butalso protects the sensing module 121 from damages by external forces.The predetermined position is located at the rearward portion of thedevice body 110, so the sensing module 121 is located at the rearwardportion of the device body 110.

Further, as shown in FIGS. 9 to 13, in order to protect the sensingmodule 121, the device body 110 further includes a protection cover1032, and the sensing module 121 is located between the accommodatingchamber 1031 and the protection cover 1032. Specifically, after thesensing module 121 is assembled into the accommodating chamber 1031, theprotection cover 1032 is further fixed to the upper housing 103 to coverthe sensing module 121. The sensing module 121 is fixed to the upperhousing 103 by a first connecting piece, and the protection cover 1032is fixed to the upper housing 103 by a second connecting piece, thusfacilitating removal of the sensing module 121 from the device body 110and realizing a purpose of modularity. Optionally, the first connectingpiece and the second connecting piece may be selected as screws, andcertainly other connecting pieces are contained in the presentdisclosure as long as they facilitate assembling and disassembling.

In an optional embodiment, the protection cover 1032 is made ofcombinational materials of high-strength nylon and glass fiber, suchthat the protection cover 1032 has strong hardness to withstand externalforces from all directions, thereby providing better protection for thesensing module 121. In the present disclosure, a circumferential side ofthe protection cover 1032 is hollowed out so as not to affect detectionof surrounding obstacles by the sensing module 121. The circumferentialside of the protection cover 1032 includes at least one column, whichshould meet a strength requirement and not be too wide to block emissionand reception of the laser beam. In some embodiments, three columns areprovided, and a width of each column is reduced as much as possible onthe premise of selecting high-strength materials. Since the protectioncover 1032 of the LDS and the upper housing 103 are separate, theprotection cover 1032 may be separately designed with the high-strengthmaterials, so as to reduce the width of the column. Typically, thesensing assembly is provided on the chassis, the protection cover andthe upper housing are integrated, and an overall design with thehigh-strength materials will cause a substantial increase in cost, sothe width of the column is relatively large, thus blocking emission andreception of the laser beam for ranging.

After the protection cover 1032 is assembled, the upper cover 104 isassembled to the upper housing 103. The upper cover 104 is provided witha clearance hole 1041 at a position corresponding to the sensing module121, the sensing module 121 partially protrudes out of the upper cover104 through the clearance hole 1041, and a part of the protection cover1032 also protrudes out of the upper cover 104 because the protectioncover 1032 covers the sensing module 121. Further, the upper cover 104includes a main cover body connected pivotably. In embodiments of thepresent disclosure, the sensing module 121 is arranged adjacent to thedust box assembly.

In a process of assembling the sensing module 121, it is unnecessary todisassemble the upper housing 103 and the bottom housing 101, only theupper cover 104 needs to be opened, and then, the sensing module 121 isfixed to the upper housing 103 by screws 1212, in which a plurality ofconnection holes 1033 corresponding to the upper housing 103 areprovided at a periphery of the sensing module 121. Alternatively, thesensing module 121 is fixed to the upper cover 104 by four screws 1212in the present disclosure. After the sensing module 121 is fixed, theprotection cover 1032 is fixed to the upper housing 103 by a pluralityof screws 1213, and covers the sensing module 121. Further, the upperhousing 103 further includes a plurality of support columns 1034, andthe plurality of support columns 1034 are correspondingly located at aperiphery of the protection cover 1032 to support the protection cover1032, such that a certain safety gap exists between the protection cover1032 and the sensing module 121, thus preventing the protection cover1032 from directly transmitting an external force to the sensing module121 when the external force is exerted on the protection cover 1032.

In a process of detaching the sensing module 121, it is unnecessary todisassemble the upper housing 103 and the chassis102 beforehand, and thesensing module 121 may be directly detached after the upper cover 104 isopened. Specifically, the protection cover 1032 is detached in advanceby unscrewing the screws 1213 with a screwdriver, and then the screws1212 are removed from the sensing module 121, such that the sensingmodule 121 may be detached or replaced directly.

In the present disclosure, the accommodating chamber 1031 for the LDSand the LDS itself both have a water drain hole, and if water entersthis space, the water will flow out from the drain hole without causingfailure of the LDS. Specifically, a waterproof and dustproof hole 1214is provided at the periphery of the sensing module 121, and a throughhole (not shown) corresponding to the waterproof and dustproof hole 1214is provided in the upper housing 103, such that the water flowing on theLDS flows downwards through the waterproof and dustproof hole 1214, andfurther flows out of the device body via the through hole in the upperhousing 103. Further, the upper housing 103 may be provided with athrough hole in a position below a motor of the LDS, and a guide groovemay be provided under the through hole to prevent water droplets fromflowing over to other positions at a lower surface.

In the present disclosure, as shown in FIG. 14 which is a bottom view ofa sensing module according to an illustrative embodiment, the sensingmodule 121 further includes a connector 1211 provided to a lower surfaceof the sensing module 121, so as to facilitate the detaching of thesensing module 121. The connector 1211 is electrically connected to acontrol component (i.e. the circuit mainboard) in the device body 110 ina hot-plug manner. The control component is located below the sensingmodule 121, and may be fixed to the chassis 102. The connector 1211 isconfigured as a vertical plug-in connector and has a certain tolerancecapability, so as to make it convenient to detach the sensing module 121and avoid a cable-organizing difficulty and a cable-crimping due to theuse of cables.

As shown in FIG. 15, the left drive wheel unit and the right drive wheelunit each include a wheel body 14111, a motor 14112, a spring 14113 anda Hall sensor 14114. When the main machine of the autonomous cleaningdevice is placed on the ground, most part of the wheel is retracted intothe device body under gravity, and the spring 14113 is stretched. Whenthe main machine is lifted from the ground, an elastic force of thespring 14113 pulls the wheel out of the device body, and the Hall sensor14114 is triggered to inform the mainboard that the device is lifted.The left drive wheel unit has a substantially same functional structureas the right drive wheel unit, and part of shape structures of the leftand right drive wheel units are adjusted due to different assemblinglocations of the left and right drive wheel units. The left drive wheelunit 1411 is taken as an example for description. The left drive wheelunit 1411 includes an upper casing 14115, a lower casing 14116 and adrive body fixed between the upper casing 14115 and the lower casing14116. The drive body includes the wheel body 14111, the motor 14112,the spring 14113 and the Hall sensor 14114. A connector (not shown) ofthe left drive wheel unit 1411 is provided to the lower casing 14116,the drive body is electrically connected to the connector through aconnecting finger 14117, and the connector is further connected to acorresponding position on the device body, so as to realize control overthe left drive wheel unit 1411. The drive body is fixed between theupper casing 14115 and the lower casing 14116 by screws.

In the present disclosure, the cleaning module in an optimumconfiguration may be obtained by improving the corresponding cleaningsystem 150 of the above-described autonomous cleaning device 100, suchthat it is possible to reduce airflow loss in the cleaning module andimprove a dust-collection efficiency under same power conditions. Thepresent disclosure will be described below with reference toembodiments.

FIG. 16 is a sectional view of a cleaning module of an autonomouscleaning device according to an illustrative embodiment. When anautonomous cleaning device shown in FIG. 17 is the autonomous cleaningdevice 100 shown in FIGS. 1 to 4 or other similar devices, the cleaningmodule of the autonomous cleaning device 100 may correspond to thecleaning system 150 of the above-described autonomous cleaning device100. For ease of description, FIG. 16 show direction information of theautonomous cleaning device in an illustrative embodiment, including theadvancing direction along the axis y (in which a left direction of theaxis y is assumed as a forward drive direction, denoted as “+”, and aright direction of the axis y is assumed as a backward drive direction,denoted as “−”) and a vertical direction along the axis z.

As shown in FIG. 16, the cleaning module is distributed within thedevice body, an air inlet of the cleaning module is provided in thebottom housing, and an air outlet of the cleaning module is provided ina side of the device body. The cleaning module of the present disclosuremay include: the main brush assembly 1, the dust box assembly 2, a powerunit 3, a primary air channel 4 and a secondary air channel 5, as shownin FIG. 21.

The main brush assembly 1, the dust box assembly 2 and the power unit 3are arranged sequentially along the advancing direction (i.e. the axisy) of the autonomous cleaning device, and the primary air channel 4 islocated between the main brush assembly 1 and the dust box assembly 2,while the secondary air channel 5 is located between the dust boxassembly 2 and the power unit 3. Thus, the cleaning module shown in FIG.16 may form an air path from the main brush assembly 1 to the drive unit3 sequentially through the primary air channel 4, the dust box assembly2 and the secondary air channel 5, such that wind generated by the powerunit 3 may flow from the main brush assembly 1 to the drive unit 3 viathe above air path, and a flow direction thereof is indicated by arrowsshown in FIG. 21. When the wind generated by the power unit 3 is flowingamong the main brush assembly 1, the primary air channel 4 and the dustbox assembly 2, the objects to be cleaned, such as dust, granularrubbish, etc., which are swept by the main brush assembly 1, may beconveyed to the dust box assembly 2 to realize a cleaning operation.

The DPU efficiency is an accurate representation of a cleaningcapability of the autonomous cleaning device, and determined by asuction efficiency and a main brush sweeping efficiency together. Thediscussion herein focuses on the suction efficiency. The suctionefficiency is an accurate representation of a dust-collection capabilityand reflects an efficiency of converting electrical energy intomechanical energy. The suction efficiency equals a ratio of a suctionpower to an input power, in which the input power refers to electricalenergy input by a fan motor, and the suction power equals a product ofan air volume and a vacuum degree. After the input power increases to acertain value, the air volume inhaled is generated. As the input powerincreases, the air volume increases and the vacuum degree decreases, butthe suction power first increases and then decreases, so the input powerworks in a range to keep the suction power relatively high.

For the same input power, the greater the air volume and the vacuumdegree are, the higher the suction efficiency may become. The reductionin loss of the vacuum degree mainly depends on the avoidance of airleakage, i.e. a sealing process. The reduction in loss of the air volumemainly depends on a smooth air path structure without abrupt changes,specifically depending on whether air from a lower end of the main brushenters the air channel without loss, the number of times of reflectingthe air by great angles in a process of the air being blown from thelower end of the main brush towards the dust box and then into the fan,and whether a great deal of turbulence is generated when a sectionalarea of the air channel changes. The overall structure of the air pathis designed as an organic whole, and a structure change of one componentwill lead to a huge change in the dust-collection efficiency of thewhole device.

As the main brush is used as the main brush assembly 1, the larger itswidth is, the greater the width of a single clean-up is. However, thedust box is used as the dust box assembly 2, it is disposed within thehousing along with the travel wheel and other components, so its widthis restricted and cannot be too large. Furthermore, in order to improvea vacuum net pressure to suck the rubbish into the dust box, an inlet ofthe dust box cannot be too wide, and hence the first air channel existsbetween the main brush and the dust box and has a tapered section. Anoutlet of the dust box is provided with a filter screen for filteringair, and a section of the outlet of the dust box is usually large toprevent blockage of the filter screen from affecting smoothness of theair channel, while a diameter of an inlet of the fan which is used asthe power unit 3 is much smaller than that of the outlet of the dustbox, such that the second air channel exists between the dust box andthe fan and also has a tapered section. These two air channels areadopted in the air path of some autonomous cleaning devices at present,but an optimal air path where the two air channels are optimized is notemployed.

Actually, the air path includes the main brush, the dust box, the fanand even two air channels with tapered sections, but the difference inthe shape of the air channel makes the suction efficiency quitedifferent.

The air path structure in the present disclosure allows air to enter theair channel from the floating lower end of the main brush. Since thefloating main brush may be tightly fitted with the ground in areas to becleaned and having different heights, the loss of the air volume islittle. The floating main brush is realized by a soft material propertyof the primary air channel and a structural design which enables themain brush to extend and retract up and down as the landform varies.

The wind enters the primary air channel through a main brushaccommodating chamber, and a shape of the primary air channel allows anet pressure value of the wind to increase smoothly, thus obliquelymoving the rubbish upwards into the dust box. An inclination degree ofthe primary air channel enables the air to be reflected by a largereflection angle at a top of the dust box and to further leave the dustbox, after the air enters the dust box. The rubbish entering the dustbox falls to a bottom of the dust box under gravity, and the air that isobliquely moving upwards and reflected by the large reflection angle atthe top of the dust box is blown out of the filer screen and then entersthe secondary air channel. A design purpose of the secondary air channelis to make the air blown out of the filter screen enter a fan port in acertain direction with as little loss as possible.

Various structures in the cleaning module are described in detail.

1. Structure of Main Brush Assembly 1

FIG. 16 is a perspective view of a main brush module in the main brushassembly, and FIG. 17 is an exploded view of the main brush module shownin FIG. 16 (FIG. 17 is observed in a view angle from the bottom up alongthe axis z). As shown in FIGS. 16-19, the main brush module includes amain brush 11 and a main brush chamber 13, and the main brush chamber 13further includes a floating system holder 131 and a main brush casing132.

1) Main Brush 11

FIG. 18 is a schematic view of the main brush 11. As shown in FIG. 18,the main brush 11 in the main brush assembly may be a rubber and hairintegrated brush, i.e. a rotating shaft 111 of the main brush 11 isprovided with a rubber brush member 112 and a hair brush member 113simultaneously, so as to be suitable for various cleaning environments,such as floors and blankets. Growing directions of rubber pieces of therubber brush member 112 and growing directions of hair tufts of the hairbrush member 113 are substantially consistent with radial directions ofthe rotating shaft 111. An entire width of the rubber pieces of therubber brush member 112 and an entire width of the hair tufts of thehair brush member 113 are substantially consistent with a width of aninlet end 41 of the primary air channel 4. In FIG. 18, a row with itsmiddle part curved upwards slightly represents one rubber brush member112, a row in a wavy shape represents one hair brush member 113, andeach main brush 11 may include at least one rubber brush member 112 andat least one hair brush member 113.

The rubber brush member 112 and the hair brush member 113 are notarranged in a parallel manner or an approximately parallel manner.Instead, a relatively large included angle is formed between the rubberbrush member 112 and the hair brush member 113 to enable them to realizetheir own application functions.

(1) Rubber Brush Member 112

Since relatively large gaps exist among hair tufts 113A of the hairbrush member 113, the wind is easily lost from the gaps, therebyresulting in less contribution to formation of a vacuum environment.Thus, by providing the rubber brush member 112, an wind-gathering effectmay be generated, to assist in sweeping the objects to be cleaned whenan wind-gathering strength reaches a preset strength, such that theobjects to be cleaned may be transmitted to the dust box assembly 2 moreconveniently under the sweeping of the main brush 11 and the blowing ofthe wind.

For example, in the embodiment shown in FIG. 18, the rubber brush member112 is arranged in such a manner that the rubber brush member 112 isarranged along an approximately straight line in a cylindrical surfaceof the main brush 11 and is curved, at its middle position, in adirection opposite to a rolling direction of the main brush 11, i.e.,the rubber brush member 112 has a first deviation angle, which isrelatively small, along a circumferential direction of the rotatingshaft 111 in the cylindrical surface of the main brush 11, such that thewind generated by the power unit 3 gathers in the middle position wherethe rubber brush member 112 is curved, so as to enable the rubber brushmember 112 to collect the objects to be cleaned. Additionally, as shownin FIG. 17, the floating system holder 131 has an arc-shaped structure1311 for guiding the air path and extending from an air intake position(i.e. a lower end in FIG. 17) to the primary air channel 4, and thearc-shaped structure 1311 has a same curvature as an arc-shape portion40 of the primary air channel 4, such that the arc-shaped structure 1311improves the efficiency of the wind entering the air channel, andreduces the loss of air volume.

(2) Hair Brush Member 13

In the embodiment of the present disclosure, the hair brush member 113(i.e., adjacent hair tufts 113A) has a second deviation angle, which isrelatively large, along the circumferential direction of the rotatingshaft 111 in the cylindrical surface of the main brush 11. For each hairbrush member 113, by providing the relatively large deviation angle,when hair tufts 113A of the hair brush member 113 are arrangedsequentially along the axial direction of the rotating shaft, a greaterangle of coverage over the main brush 11 is achieved in thecircumferential direction. For example, the circumferential angle ofcoverage over the main brush 11 reaches a preset angle.

On one hand, by enlarging the circumferential angle of coverage over themain brush 11, a cleaning degree and a cleaning efficiency may beimproved. The main brush 11 cleans the ground in a rolling processthereof, however only when the circumferential angle of coverage overthe main brush 11 by the hair brush member 113 reaches 360 degrees, canit be ensured that the main brush 11 implements the cleaning operationthroughout the rolling process.

On the other hand, the hair brush member 113 needs to touch the groundfor sweeping in the cleaning process, in which the hair brush member 113has a certain deformation due to its soft characteristics and hencegenerates a “support” effect on the whole autonomous cleaning device. Ifthe circumferential angle of coverage over the main brush 11 by the hairbrush member 113 is not sufficient, a height difference is formedbetween an area within the circumferential coverage and an area out ofthe circumferential coverage, thus leading to jolt and shake of theautonomous cleaning device in the axis z and affecting theimplementation of the cleaning operation. Therefore, when the hair brushmember 113 is able to achieve a 360-degree circumferential coverage overthe main brush 11, the jolt and shake of the main brush 11 may beeliminated, which ensures that the autonomous cleaning device maintainsa continuous and stable output, reduces noises generated by theautonomous cleaning device, avoids impact to the motor, and prolongs aservice life of the autonomous cleaning device.

2) Main Brush Casing 122

FIG. 19 shows a perspective view of the main brush casing 132 in suchmain brush assembly. This main brush casing 132 may include ananti-winding guard 1321 and a flexible rubber wiping strip 1322 locatedbehind the anti-winding guard 1321 in the advancing direction. On onehand, the anti-winding guard 1321 may block the objects having big sizesfrom entering the air channel and blocking the air channel, and on theother hand, the anti-winding guard 1321 may also block elongatedobjects, such as wires, from entering the main brush chamber 13 andresulting in winding.

With reference to FIG. 16, it can be known that the main brush casing132 is located below the main brush 11 along the axis z, and blocks theoversized objects from being carried into the main brush assembly andaffecting the normal cleaning operation. The flexible rubber wipingstrip 1322 is located below the anti-winding guard 1321 in the axis zand at a tail end of the main brush casing 132 along the advancingdirection, such that the flexible rubber wiping strip 1322 maintains acertain distance (like 1.5 to 3 mm) away from the main brush 11.Moreover, the flexible rubber wiping strip 1322 is closely fitted withthe ground to intercept and collect a small number of objects to becleaned that have not been directly swept up by the main brush 11, suchthat the small number of objects may be carried along between the mainbrush 11 and the main brush chamber 13, and thus enter the primary airchannel 4, under the sweeping of the main brush 11 and the blowing ofthe wind. The position and angle of the flexible rubber wiping strip1322 are selected in such a manner that the objects to be cleaned arealways located at optimal cleaning and suction positions, therebypreventing any rubbish from being left after the cleaning of theflexible rubber wiping strip 1322.

As shown in FIG. 19, at a tail end of the anti-winding guard 1321 alongthe advancing direction, i.e. a right end of the anti-winding guard1321, the anti-winding guard 1321 may be provided with anobstacle-crossing assisting member 1321A in cooperation with theadvancing direction of the autonomous cleaning device. On one hand, theobstacle-crossing assisting member 1321A may assist the autonomouscleaning device in surmounting obstacles, and on the other hand, theobstacle-crossing assisting member 1321A may abut against an uppersurface of the flexible rubber wiping strip 1322, so as to make a bottomedge of the flexible rubber wiping strip 1322 always closely fitted witha surface to be cleaned (such as the ground, a table top, etc.) when theautonomous cleaning device is in the working state, and further toprevent the flexible rubber wiping strip 1322 from being rolled up bythe obstacles (like rubbish) on the surface to be cleaned, therebyguaranteeing a subsequent cleaning effect.

In an embodiment, the obstacle-crossing assisting member 1321A may beconfigured as a protrusion protruding downwards (i.e. along a negativedirection of the axis z, shown as “up” in FIG. 19) from the tail end ofthe anti-winding guard 1321 along the advancing direction.

3) Floating System Holder 131

As shown in FIG. 20, the floating system holder 131 may include a fixedholder portion 1312 and a floating holder portion 1313, and is furtherprovided with the primary air channel 4 and a main brush motor 1314. Twomounting holes 1312A are provided in the fixed holder portion 1312 in aleft-and-right direction, and two mounting shafts 1313A are provided tothe floating holder portion 1313 in the left-and-right direction, suchthat the floating holder portion 1313 can “float” along the up-and-downdirection by position limitation and rotation fit between each mountingshaft 1313A and the corresponding mounting hole 1312A.

Therefore, when the autonomous cleaning device is in a normal sweepingprocess, the floating holder portion 1313 rotates to the lowest positionunder gravity, and regardless of the floor, the blanket or otherunsmooth surfaces to be cleaned, the main brush 11 mounted in thefloating system holder 131 may be closely fitted with the surface to becleaned within a floating path range of the main brush 11, thusrealizing the most efficient sweeping in a ground-close-fit manner(i.e., being closely fitted with the ground during sweeping). That is,the main brush 11 has a great ground-close-fit effect regardingdifferent types of surfaces to be cleaned, and hence makes significantcontribution to airtightness of the air channel.

When an obstacle 6 exists on the surface to be cleaned, through theupward and downward “floating” of the floating holder portion 1313,mutual interaction between the main brush 11 and the obstacle 6 may bereduced, so as to assist the autonomous cleaning device in surmountingthe obstacle easily. The primary air channel 4 is located between thefixed holder portion 1312 and the floating holder portion 1313, so thefloating main brush 11 proposes a requirement for flexibility of theprimary air channel 4, because a rigid air channel cannot absorbfloating changes of the main brush 11, and the requirement is realizedby soft materials of the primary air channel 4. Thus, when the primaryair channel 4 is made of the soft materials (e.g. soft rubber), in anobstacle-crossing process, the floating holder portion 1313 extrudes theprimary air channel 4 and cause deformation of the primary air channel4, so as to realize the upward “floating” smoothly.

Additionally, in the normal sweeping process, as for a rough surface tobe cleaned, like the blanket, the “floating” function of the floatingholder portion 1313 may reduce mutual interference between the mainbrush 11 and the blanket, thus reducing resistance against the mainbrush motor 1314, so as to decrease power consumption of the main brushmotor 1314 and prolong a service life thereof.

2. Structure of Primary Air Channel 4

In the present disclosure, through guidance of the primary air channel4, the wind generated by the power unit 3 may transmit the objects to becleaned, such as dust swept up by the main brush assembly 1, into thedust box assembly 2.

In terms of the overall structure, as shown in FIG. 21, the primary airchannel 4 may be configured to have a flared shape, and a sectional areaof the primary air channel 4 corresponding to any position on theprimary air channel 4 is in a negative relationship with a distancebetween the any position and the main brush assembly 1. In other words,a relatively large side of the “flared” shape faces the main brushassembly 1, while a relatively small side thereof faces the dust boxassembly 2.

In this embodiment, the sectional area of the primary air channel 4gradually decreases from the main brush assembly 1 to the dust boxassembly 2, a static pressure at the corresponding position along theprimary air channel 4 is gradually increased therewith, i.e. the suctionforce becomes greater and greater from the main brush assembly 1 to thedust box assembly 2. Thus, after the objects to be cleaned, such as dustand rubbish, are swept up and brought to the primary air channel 4 bythe main brush assembly 1, the objects to be cleaned gradually departfrom the main brush assembly 1 and approach to the dust box assembly 2(similarly approaching to the power unit 3 gradually). Although asweeping force exerted on the objects to be cleaned by the main brushassembly 1 decreases gradually, the suction force exerted on the objectsto be cleaned by the power unit 3 increases gradually, such that it isensured that the objects to be cleaned can be sucked and transmittedinto the dust box assembly 2.

Further, as shown in FIG. 21, the inlet end 41 of the primary airchannel 4 faces the main brush 11 of the main brush assembly, and awidth of the inlet end 41 in a horizontal plane along a direction (i.e.the axis x) perpendicular to the advancing direction is increasedgradually from up to down. For ease of understanding, regarding the fitrelationship between the primary air channel 4 and the main brush 11shown in FIG. 21, FIG. 22 shows a perspective view of the primary airchannel 4 fitted with the main brush 11. As shown in FIG. 22, the inletend 41 of the primary air channel 4 close to the main brush 11 has alarger sectional area, while an outlet end 42 thereof away from the mainbrush 11 has a smaller sectional area. Based on the above “graduallyincreased” width of the inlet end 41, a section of the inlet end 41 mayhave a trapezoid shape, a narrower second edge 412 of the inlet end 41is an upper bottom edge of the trapezoid, and a wider first edge 411 ofthe inlet end 41 is a lower bottom edge of the trapezoid. Certainly, thesection of the inlet end 41 may have other shapes as well, as long asthe above “gradually increased” width is satisfied, which is not limitedin the present disclosure.

In the embodiment, the inlet end 41 of the primary air channel 4 adoptsthe trapezoid shape or similar shapes that meet the above “graduallyincreased” width, such that the static pressure at the correspondingposition in the inlet end 41 increases accordingly. Hence, when theobjects to be cleaned, such as dust and rubbish, are swept up andbrought to the inlet end 41 by the main brush 11, the wind generated bythe power unit 3 may provide sufficient suction force, such that theobjects swept to the inlet end 41 may be sucked into the dust boxassembly 2 as much as possible, which is conductive to improving thecleaning efficiency.

As shown in FIG. 21, the inlet end 41 of the primary air channel 4 maybe connected to the main brush chamber 13 of the main brush assembly 1.As shown in FIG. 23, the primary air channel 4 includes two side wallsin a rolling direction of the main brush 11, i.e. a first side wall 43located at a rear side in the advancing direction, and a second sidewall 44 located at a front side in the advancing direction, and the twoside walls may be configured as follows.

1) First Side Wall 43

In an embodiment, the first side wall 43 may be provided along atangential direction of a circular section region of the main brushchamber 13. For example, as shown in FIG. 23, the main brush chamber 13may include multiple portions in section, such as a left arc-shapedstructure and a right L-shaped structure, in which an arc portion of theleft arc-shaped structure corresponds to a circular dotted region shownin FIG. 23, so the circular dotted region corresponding to the arcportion may be equivalent to the above circular section region.Correspondingly, the first side wall 43 of the primary air channel 4 maybe provided along a tangential direction of the circular dotted region.For example, in a relative position relationship shown in FIG. 23, sincethe primary air channel 4 is located obliquely above the main brushassembly and leans to a rear side of the main brush 11 in the advancingdirection, the first side wall 43 may be disposed along a verticaldirection.

In this embodiment, after the main brush 11 sweeps up the objects to becleaned from the ground, the objects to be cleaned first move along agap between the main brush 11 and the main brush chamber 13. As theobjects to be cleaned move from the main brush structure to the primaryair channel 4, by disposing the first side wall 43 along the abovetangential direction, a movement track of the objects to be cleaned andan air flow are not blocked by the first side wall 43, thus ensuringthat the objects to be cleaned can smoothly enter the dust box assembly2 through the primary air channel 4.

2) Second Side Wall 44

In an embodiment, combining FIG. 21 with FIG. 23, the primary airchannel 4 leans to the rear side of the main brush 11 in the advancingdirection, the inlet end 41 of the primary air channel 4 faces the mainbrush 11 located obliquely below the front side (e.g. a left side inFIG. 21) of the advancing direction, the outlet end 42 thereof isconnected to an air inlet 211 of the dust box assembly 2 locatedobliquely above the rear side (e.g. a right side in FIG. 21) of theadvancing direction, and an air outlet 212 of the dust box assembly 2 islocated at a non-top side (i.e. the air outlet 212 is not located at thedust box top 214, and for example, the air outlet 212 is located at aright side wall in FIG. 21).

The second side wall 44 of the primary air channel 4 inclines obliquelyrearwards towards the horizontal plane (i.e. approaching the horizontalplane as close as possible), i.e. the second side wall 44 forms anincluded angle as large as possible with the vertical direction in theaxis z. Actually, due to a limited internal space within the autonomouscleaning device, the main brush structure, the primary air channel 4 andthe dust box assembly 2 are arranged in a very compact manner, and themost space-saving way is to arrange the primary air channel 4 completelyalong the axis z, but the air volume will be lost considerably, therebyreducing the suction efficiency greatly. However, in the embodiment ofthe present disclosure, in the case of limited internal space, byincreasing the included angle between the second side wall 44 and theaxis z, the wind may be obliquely guided upwards, such that the wind isreflected by the large angle at the dust box top 214 after entering thedust box assembly 2, and is further discharged out in an approximatelyhorizontal direction through the filter screen 22 at the air outlet 212.Such air path design with one large-angle reflection reduces the loss ofair volume.

Furthermore, since the inlet end 41 of the primary air channel 4 facesthe main brush 11 at a left lower side, and the outlet end 42 thereof isconnected to the air inlet 211 of the dust box assembly 2, the wind andentrained objects to be cleaned may be blown directly to the dust boxtop 214 of the dust box assembly 2 when the primary air channel 4 guidesthe wind into the dust box assembly 2. Since the air outlet 212 of thedust box assembly 2 is not located at the dust box top 214, when thewind is blown directly towards the dust box top 214, the wind needs tobe reflected with a large incident angle at the dust box top 214, andfurther enters the secondary air channel 5 through the air outlet 212after an wind direction change. After the wind enters the dust boxassembly 2, the sectional area becomes large, so a wind speed islowered, and the objects to be cleaned fall from the dust box top 214due to the decrease in the wind speed and remain in the dust boxassembly 2. Meanwhile, due to the reduction of the wind speed and thechange of the wind direction, the wind cannot continue blowing theobjects to be cleaned to the air outlet 212, although the wind itselfmay be blown to the air outlet 212 and enters the secondary air channel5, so when the air outlet 212 of the dust box assembly 2 is providedwith the filter screen 22, it is possible to prevent the objects to becleaned from being directly blown to the filter screen 22 and blockingthe filter screen 22, thus improving a utilization rate of the airvolume.

3. Dust Box Assembly 2

As shown in FIG. 24, a dust-box accommodating chamber 14 is provided ina top of the device body 110, and the dust box assembly 2 may be placedinto the dust-box accommodating chamber 14 to be mounted to the devicebody 110. Certainly, the dust-box accommodating chamber 14 may belocated at other positions of the device body 110, for example, at aside edge in the rear of the device body 110 (referring to a rear sideof the axis y shown in FIG. 4), which is limited in the presentdisclosure.

As shown in FIG. 24, to achieve an in-position detection of the dust boxassembly 2, the dust box assembly 2 may be provided with a non-contactinductive element 31, and the device body 110 may be provided with anon-contact inductive cooperating element 32. The non-contact inductiveelement 31 and the non-contact inductive cooperating element 32 mayachieve a non-contact cooperative induction in a certain range, so thereis no need of complex mechanical structure and assembling relationship,as long as it is ensured that the non-contact inductive element 31 is ina sensible distance from the non-contact inductive cooperating element32, the cooperative induction between the both may be realized, therebyrealizing the in-position detection of the dust box assembly 2.

Therefore, by configuring the sensible distance between the non-contactinductive element 31 and the non-contact inductive cooperating element32 in advance, when the dust box assembly 2 is mounted to the devicebody 110, the non-contact inductive element 31 may cooperate with thenon-contact inductive cooperating element 32, and the non-contactinductive cooperating element 32 may sense the non-contact inductiveelement 31. As a result of a non-contact induction adopted between theboth, it is possible to avoid squeezing, breaking, material aging andother unexpected circumstances caused in the assembling process andhence to improve reliability in an application process, compared with amechanical structure that needs mutual assembling each time.

In an illustrative embodiment, the non-contact inductive element 31 maybe a magnetic sheet, and the non-contact inductive cooperating element32 may be a Hall sensor. By configuring a cooperative relationshipbetween the magnetic field strength of the magnetic sheet and theinductive sensitivity of the Hall sensor, when the dust box assembly 2is mounted to the device body 110, the Hall sensor may exactly sense themagnetic sheet, so as to realize the in-position detection of the dustbox assembly 2 by the magnetic sheet.

Certainly, as said above, the present disclosure does not limit aninductive direction between the non-contact inductive element 31 and thenon-contact inductive cooperating element 32, so similar to the aboveembodiment, the Hall sensor may serve as the non-contact inductiveelement 31 and be mounted in the dust box assembly 2, and the magneticsheet may serve as the non-contact inductive cooperating element 32 andbe mounted to the device body 110, which may realize the abovein-position detection as well and will not be illustrated again.

In the present disclosure, the non-contact inductive element 31 may bemounted at any position in the dust box assembly 2, which is not limitedin the present disclosure. Similarly, the non-contact inductivecooperating element 32 may be mounted at any position in the device body110, which is not limited in the present disclosure, either. However,for the non-contact inductive element 31, by changing its installationposition in the dust box assembly 2, different in-position detectioneffects may be achieved.

As shown in FIG. 25, the dust box assembly 2 includes the dust box 21and the filter screen 22, and the filter screen 22 is detachably mountedto the dust box 21, so there are two ways of mounting the non-contactinductive element 31, i.e. being mounted in the dust box 21 or beingmounted to the filter screen 22.

Supposing that the non-contact inductive element 31 is mounted to thefilter screen 22, it is impossible for the user to separately mount thefilter screen 22 to the device body 110 and overlook the dust box 22,because sizes and shapes of the filter screen 22 and the dust box 21 aregreatly different. Thus, there are two installation situations: (1) theuser separately mounts the dust box 21 to the device body 110 withoutmounting the filter screen 22 to the dust box 21, in which case theautonomous cleaning device cannot detect the dust box assembly 2 becausethe non-contact inductive element 31 is located on the filter screen 22,and hence a detection result is that the dust box assembly 2 is not inposition; (2) the user mounts the filer screen 22 to the dust box 21,and the autonomous cleaning device may determine that the dust boxassembly 2 is in position after the user mounts the complete dust boxassembly 2 to the device body 110.

Therefore, by mounting the non-contact inductive element 31 to thefilter screen 22, it is possible to carry out the in-position detectionof the whole dust box assembly 2, and also detect the filter screen 22,so as to ensure that the dust box assembly 2 indeed includes the dustbox 21 and the filter screen 22 when the autonomous cleaning deviceobtains a detection result reading that “the dust box assembly 2 is inposition”, thereby preventing the wind from being blown into the fanstructure without being filtered by the filter screen 22, and furtherpreventing dust, granular rubbish and the like from being blown into thefan structure and causing damages to the fan structure. Since theaccumulation of dust on the filter screen 22 greatly reduces the airvolume and hence affects the dust-collection efficiency, the filterscreen 22 often needs to be cleaned by the user to keep a clean air pathunobstructed. After cleaning the filter screen 22, the user is mostlikely to forget to put it back and directly place the dust box 21 intothe device body 110, in which case the dust and rubbish may enter thefan structure and cause damages to the fan structure once the autonomouscleaning device is started to sweep. In fact, it is not rare for theautonomous cleaning device, such as a sweeping robot, that the fantherein is ruined just because the filter screen 22 is forgotten to bemounted. Due to a sheet-like structure of the filter screen 22, it isdifficult to provide a mechanical element on the filter screen 22 forin-position identification.

Optionally, the non-contact inductive element 31 may be mounted at anyposition on a frame of the filter screen 22. For example, the magneticsheet is embedded in a plastic frame of the filter screen 22.

In the present disclosure, two side openings may be formed in the dustbox 21, one side opening is configured as the air inlet 211 in the dustbox 21, and the other side opening is configured as the air outlet 212in the dust box 21, as shown in FIG. 26. The filter screen 22 may bemounted at the air outlet 212, and by covering the air outlet 212 withthe filter screen 22, it is ensured that the objects to be cleaned, suchas dust, remain in the dust box 21, thus preventing the objects to becleaned from being blown through the air outlet 212 to the subsequentfan structure.

In an illustrative embodiment, as shown in FIG. 26, the dust box 21 maybe further split into a dust box body 21A and a side wall 21B providedwith the air inlet 211. Since the air inlet 211 is provided in the sidewall 21B, a size of the side wall 21B is necessarily larger than that ofthe air inlet 211, and thus, after the side wall 21B is removed, adumping port 213 larger than the air inlet 211 in size may be formed tomake it convenient for the user to dump the objects to be cleaned (suchas dust) collected in the dust box 21.

4. Smooth Guidance of Secondary Air Channel 5

FIG. 27 is a top view of the air path structure shown in FIG. 21. Asshown in FIG. 27, the main brush assembly 1, the dust box assembly 2 andthe power unit 3 are arranged sequentially along the advancing direction(i.e. the axis y) of the autonomous cleaning device, and also, the dustbox assembly 2 and the power unit 3 are offset from each other in theaxis x (i.e. the left-and-right direction of the autonomous cleaningdevice), such that when the wind is blown from the dust box assembly 2to the power unit 3, the wind moves in the axis y (i.e. “from left toright” in FIG. 17) and in the axis x (i.e. “from down to up” in FIG. 17)simultaneously, that is, the wind makes a turn in a flowing processthereof. The dust box assembly 2 and the power unit 3 may not be offsetfrom each other in the axis x, which is not limited in the presentdisclosure.

As shown in FIG. 27, the secondary air channel 5 has a flared shape (asectional area of the secondary air channel 5 close to the dust boxassembly 2 is relatively large, and a sectional area of the secondaryair channel 5 close to the power unit 3 is relatively small) to gatherthe wind to the air inlet of the power unit 3. When the wind is blownfrom the dust box assembly 2 to the secondary air channel 5, the wind isdirectly blown to an inner wall of a windward side 51 of the secondaryair channel 5 due to the decrease of the sectional area. Thus, in thepresent disclosure, the inner wall of the windward side 51 of thesecondary air channel 5 is configured to have an arc shape, which on onehand may guide the wind output from the dust box assembly 2 in the axisx to allow the wind to be blown to the air inlet of the power unit 3,and on the other hand cooperate with the wind flow to avoid blocking orinterfering the wind flow and resulting in turbulence, thus reducing theairflow loss and improving the utilization rate of the air volume.

Meanwhile, combining FIG. 21 with FIG. 27, after being swept up by themain brush assembly 1, the objects to be cleaned are transmitted to thedust box assembly 2 by the wind generated by the power unit 3 (as wellas cooperation of the structure of the primary air channel 4), and henceby improving the utilization rate of the air volume of the air pathstructure and reducing the airflow loss, a capability of transmittingthe objects to be cleaned by the wind may be enhanced, so as to improvethe cleaning degree and the cleaning efficiency of the autonomouscleaning device.

5. Oblique Configuration of Power Unit 3

FIG. 28 is a sectional view of a secondary air channel and a power unitaccording to an illustrative embodiment. As shown in FIG. 28, an end ofthe secondary air channel 5 away from the dust box assembly 2 (notshown) has an air outlet 52, and the air outlet 52 is fitted with andconnected to an air intake 311 of the power unit 3. A plane where theair outlet 52 is located intersects with the horizontal plane, i.e. theair outlet 52 is inclined with respect to the horizontal plane. Thus,when the power unit 3 is configured as an axial-flow fan, and the airintake 311 is oriented in the same direction as a rotating shaft (anaxial direction of the rotating shaft may refer to a direction indicatedby a dotted line in FIG. 28) of the axial-flow fan, it is actuallyembodied that the axial-flow fan is inclined with respect to thehorizontal plane.

When a plane where the air outlet 52 and the air intake 311 are locatedis perpendicular to the horizontal plane, in a process that the windflows inside the secondary air channel 5 and flows from the secondaryair channel 5 into the power unit 3, the wind mainly flows in thehorizontal plane, such that when the wind is blown from the secondaryair channel 5 into the axial-flow fan, the wind direction issubstantially parallel to the axial direction of the rotating shaft, andthus the axial-flow fan used as the power unit 3 may achieve a maximumconversion efficiency (e.g. an efficiency of converting electricalenergy into wind energy). When the plane where the air outlet 52 and theair intake 311 are located is parallel to the horizontal plane, the windflows substantially along the horizontal plane inside the secondary airchannel 5, but the wind turns to flow along the vertical direction whenentering the power unit 3 from the secondary air channel 5, such thatthe axial-flow fan used as the power unit 3 has a minimum conversionefficiency.

However, due to the limited internal space in the autonomous cleaningdevice, it is impossible to realize that the plane where the air outlet52 and the air intake 311 are located is perpendicular to the horizontalplane, so in the present disclosure, by increasing an included anglebetween the axial-flow fan used as the power unit 3 and the horizontalplane, on one hand, the internal space in the autonomous cleaning devicemay be utilized reasonably, and on the other hand, the conversionefficiency of the axial-flow fan may be maximized as much as possible.

In the present disclosure, regarding a process that the wind flows inthe secondary air channel 5, a side all of the secondary air channel 5facing the air outlet 52 may protrude outwards to increase a capacity ofan inner chamber of the secondary air channel 5 at the air outlet 52,such that an energy loss of the wind generated by the power unit 3 atthe air outlet 52 is less than a predetermined loss. For example, FIG.29 is a right view of the air path structure shown in FIG. 21. As shownin FIG. 29, when the air outlet 52 is located at a top side of thesecondary air channel 5, the side wall of the secondary air channel 5facing the air outlet 52 is a bottom wall and thus may protrudedownwards to form a convex structure 53 as shown in FIG. 29, therebyincreasing the capacity of the inner chamber of the secondary airchannel 5 at the air outlet 52. Thus, when the wind direction is changedat the air outlet 52 (in the condition that the plane where the airoutlet is located is not perpendicular to the horizontal plane) and thewind is blown into the power unit 3, a larger buffer space is providedto reduce the energy loss of the wind at the air outlet 52.

6. Fully Sealed Air Channels of the Whole Device

It can be known from the foregoing analysis that the vacuum degree andthe air volume both contribute significantly to a high suctionefficiency. In the present disclosure, a sealing treatment is applied toall the gaps at joints of various parts in the air path structure, forexample, filling the gaps with flexible glue to avoid air leakage, thusreducing the loss of the vacuum degree. Furthermore, a soft rubber pieceis used at the air outlet of the fan to guide the wind completely out ofthe main machine. The soft rubber piece 3132 avoids the air leakage(i.e. lowering the vacuum degree), and further prevents dust fromentering the motor in the autonomous cleaning device, thus extending theservice life of the autonomous cleaning device.

Various functional modules of the autonomous cleaning device in thepresent disclosure are respectively mounted in accommodating spacesreserved in the device body, and may be removed separately from thedevice body, such that it is convenient to separately remove a damagedfunctional module to repair it or replace it with a new one, whichimproves a maintenance efficiency of the autonomous cleaning devicegreatly.

Other embodiments of the present disclosure will be apparent to thoseskilled in the art from consideration of the specification and practiceof the disclosure disclosed here. This application is intended to coverany variations, uses, or adaptations of the disclosure following thegeneral principles thereof and including such departures from thepresent disclosure as come within known or customary practice in theart. It is intended that the specification and examples be considered asexemplary only, with a true scope and spirit of the present disclosurebeing indicated by the following claims.

It will be appreciated that the present disclosure is not limited to theexact construction that has been described above and illustrated in theaccompanying drawings, and that various modifications and changes can bemade without departing from the scope thereof. It is intended that thescope of the disclosure only be limited by the appended claims.

What is claimed is:
 1. An autonomous cleaning device, comprising: adevice body; and a drive module, a cleaning module and a sensing module,wherein the drive module, the cleaning module and the sensing module aredetachably assembled to the device body, respectively.
 2. The autonomouscleaning device according to claim 1, wherein the device body comprises:a chassis, the drive module being mounted on the chassis; and an upperhousing fixed to the chassis, the sensing module being assembled to apredetermined position in the upper housing.
 3. The autonomous cleaningdevice according to claim 2, wherein the predetermined position in theupper housing comprises an accommodating chamber matching with thesensing module.
 4. The autonomous cleaning device according to claim 3,wherein the sensing module is fixed to the upper housing through aplurality of first connecting pieces.
 5. The autonomous cleaning deviceaccording to claim 3, wherein the device body further comprises: aprotection cover assembled above the accommodating chamber, acircumferential side of the protection cover being hollowed out, and thesensing module being located between the accommodating chamber and theprotection cover.
 6. The autonomous cleaning device according to claim5, wherein the circumferential side of the protection cover comprises atleast one column, and the width of the at least one column is reduced tomeet a strength requirement and a laser beam emission and receptionrequirement.
 7. The autonomous cleaning device according to claim 5,wherein the protection cover is fixed to the upper housing through aplurality of second connecting pieces.
 8. The autonomous cleaning deviceaccording to claim 1, wherein a waterproof and dustproof hole isprovided in a periphery of the sensing module, and the upper housing isprovided with a through hole corresponding to the waterproof anddustproof hole.
 9. The autonomous cleaning device according to claim 1,wherein the device body further comprises an upper cover, and thesensing module partially protrudes out of the upper cover.
 10. Theautonomous cleaning device according to claim 1, wherein the device bodyfurther comprises a control unit located below the sensing module, andthe sensing module comprises a connector provided at a lower surface ofthe sensing module and electrically connected with the control unit. 11.The autonomous cleaning device according to claim 1, wherein the devicebody comprises: a forward portion; and a rearward portion, the sensingmodule being located at the rearward portion.
 12. The autonomouscleaning device according to claim 1, wherein the drive modulecomprises: a drive wheel module comprising a left drive wheel unit and aright drive wheel unit, the left drive wheel unit and the right drivewheel unit being opposed to each other along a transverse axis definedby the device body.
 13. The autonomous cleaning device according toclaim 12, wherein the drive module further comprises at least one drivenwheel configured to assist in supporting and moving the device body. 14.The autonomous cleaning device according to claim 1, wherein thecleaning module comprises: a main brush assembly, a dust box assemblyand a power unit arranged sequentially along an advancing direction ofthe autonomous cleaning device; a primary air channel provided betweenthe main brush assembly and the dust box assembly, wherein the primaryair channel cooperates with the power unit such that an object to becleaned by the main brush assembly is conveyed by the wind generated bythe power unit to the dust box assembly; and a secondary air channelprovided between the dust box assembly and the power unit, wherein thewindward side of an inner wall of the secondary air channel has an arcshape, and the secondary air channel cooperates with the power unit suchthat the wind output from the dust box assembly is guided smoothly to anair intake of the power unit in a predetermined direction.
 15. Theautonomous cleaning device according to claim 14, wherein the primaryair channel comprises: a sectional area corresponding to any position onthe primary air channel, the sectional area being in a negativerelationship with a distance between the any position and the main brushassembly.
 16. The autonomous cleaning device according to claim 15,wherein the secondary air channel comprises: an air outlet connected tothe air intake of the power unit, the power unit being an axial-flow fanand the air intake of the power unit being oriented in a same directionas a rotating shaft of the axial-flow fan.
 17. The autonomous cleaningdevice according to claim 14, wherein the main brush assembly comprises:a main brush chamber; and a main brush comprising: a rotating shaft; arubber brush member provided on the rotating shaft, wherein the rubberbrush member has a first deviation angle along a circumferentialdirection of the rotating shaft in a cylindrical surface of the mainbrush to make a wind-gathering strength of the rubber brush member reacha preset strength; a hair brush member provided on the rotating shaft,wherein the hair brush member has a second deviation angle along thecircumferential direction of the rotating shaft in the cylindricalsurface of the main brush, such that when hair tufts of the hair brushmember are arranged sequentially along the axial direction of therotating shaft, a circumferential angle of coverage over the main brushin the cylindrical surface of the main brush reaches a preset angle. 18.The autonomous cleaning device according to claim 17, wherein the rubberbrush member is curved at a middle position thereof along the advancingdirection, such that the wind generated by the power unit collects theobject to be cleaned in the middle position of the rubber brush member,and the middle position of the rubber brush member reaches the primaryair channel later than other positions thereof when the autonomouscleaning device advances.
 19. The autonomous cleaning device accordingto claim 14, wherein the dust box assembly comprises: a dust boxcomprising at least two side openings, one side opening being an airinlet of the dust box and the other side opening being an air outlet ofthe dust box; a filter screen mounted at the air outlet of the dust boxfor covering the air outlet of the dust box.
 20. The autonomous cleaningdevice according to claim 19, wherein the sensing module is disposedadjacent to the dust box.